21 Foot Rule

With knives, it used to be a 21-foot rule. If someone had a knife and they were within 21 feet of you—and I’ve seen this done in studies with a rubber knife—that person can run at you and get one slice or stab on you before you can draw your weapon and fire accurately. That’s now been increased closer to 30 feet to make it safer for the officers. http://hopkins.patch.com/articles/the-right-time-to-shoot